On Fri, 25 Sep 2020, Richard Sandiford wrote:
> Richard Biener <rguent...@suse.de> writes:
> >> What do we allow for non-boolean constructors. E.g. for:
> >>
> >> v2hi = 0xf001;
> >>
> >> do we allow the CONSTRUCTOR to be { 0xf001 }? Is the type of an
> >> initialiser value allowed to be arbitrarily different from the type
> >> of the elements being initialised?
> >>
> >> Or is there requirement that (say) each constructor element is either:
> >>
> >> - a scalar that initialises one element of the constructed vector
> >> - a vector of N elements that initialises N elements of the constructed
> >> vector
> >>
> >> ?
> >>
> >> Like you say, it mostly seems like guesswork how booleans would be
> >> handled here, but personally I don't know the answer for non-booleans
> >> either :-)
> >
> > There's extensive checking in tree-cfg.c for vector CTORs meanwhile.
> > We only supporm uniform element CTORs with only trailing zeros elided.
> > And the elements need to either have types of the vector component
> > or be vectors with such component.
>
> Ah, great. So in that case, could we ditch bitsize altogether and
> just use:
>
> unsigned int nelts = (VECTOR_TYPE_P (val_type)
> ? TYPE_VECTOR_SUBPARTS (val_type).to_constant () : 1);
>
> or equivalent to work out the number of elements being initialised
> by each constructor element?
But
store_constructor_field (target, bitsize, bitpos, 0,
bitregion_end, value_mode,
value, cleared, alias, reverse);
still wants the bits to initialize (for the original testcase
the vector<bool:1> had only the first 4 elements initialized,
at wrong bit positions and sizes - QImode).
But yes, I'm sure we can eventually simplify this further.
FYI, the following passed bootstrap, regtest is still running
(but as said, test coverage dropped to zero).
Richard.
commit d16b5975ca985cbe97698479fc38b6a636886978
Author: Richard Biener <rguent...@suse.de>
Date: Fri Sep 25 11:13:13 2020 +0200
middle-end/96814 - fix VECTOR_BOOLEAN_TYPE_P CTOR RTL expansion
The RTL expansion code for CTORs doesn't handle VECTOR_BOOLEAN_TYPE_P
with bit-precision elements correctly as the testcase shows before
the PR97085 fix. The following makes it do the correct thing
(not 100% sure for CTOR of sub-vectors due to the lack of a testcase).
The alternative would be to assert such CTORs do not happen (and also
add IL verification for this).
The GIMPLE FE needs a way to declare the VECTOR_BOOLEAN_TYPE_P vectors
(thus the C FE needs that).
2020-09-25 Richard Biener <rguent...@suse.de>
PR middle-end/96814
* expr.c (store_constructor): Handle VECTOR_BOOLEAN_TYPE_P
CTORs correctly.
* gcc.target/i386/pr96814.c: New testcase.
diff --git a/gcc/expr.c b/gcc/expr.c
index 1a15f24b397..1c79518ee4d 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -6922,7 +6922,7 @@ store_constructor (tree exp, rtx target, int cleared,
poly_int64 size,
insn_code icode = CODE_FOR_nothing;
tree elt;
tree elttype = TREE_TYPE (type);
- int elt_size = tree_to_uhwi (TYPE_SIZE (elttype));
+ int elt_size = vector_element_bits (type);
machine_mode eltmode = TYPE_MODE (elttype);
HOST_WIDE_INT bitsize;
HOST_WIDE_INT bitpos;
@@ -6987,6 +6987,15 @@ store_constructor (tree exp, rtx target, int cleared,
poly_int64 size,
}
}
+ /* Compute the size of the elements in the CTOR. It differs
+ from the size of the vector type elements only when the
+ CTOR elements are vectors themselves. */
+ tree val_type = TREE_TYPE (CONSTRUCTOR_ELT (exp, 0)->value);
+ if (VECTOR_TYPE_P (val_type))
+ bitsize = tree_to_uhwi (TYPE_SIZE (val_type));
+ else
+ bitsize = elt_size;
+
/* If the constructor has fewer elements than the vector,
clear the whole array first. Similarly if this is static
constructor of a non-BLKmode object. */
@@ -7001,11 +7010,7 @@ store_constructor (tree exp, rtx target, int cleared,
poly_int64 size,
FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
{
- tree sz = TYPE_SIZE (TREE_TYPE (value));
- int n_elts_here
- = tree_to_uhwi (int_const_binop (TRUNC_DIV_EXPR, sz,
- TYPE_SIZE (elttype)));
-
+ int n_elts_here = bitsize / elt_size;
count += n_elts_here;
if (mostly_zeros_p (value))
zero_count += n_elts_here;
@@ -7045,7 +7050,6 @@ store_constructor (tree exp, rtx target, int cleared,
poly_int64 size,
HOST_WIDE_INT eltpos;
tree value = ce->value;
- bitsize = tree_to_uhwi (TYPE_SIZE (TREE_TYPE (value)));
if (cleared && initializer_zerop (value))
continue;
diff --git a/gcc/testsuite/gcc.target/i386/pr96814.c
b/gcc/testsuite/gcc.target/i386/pr96814.c
new file mode 100644
index 00000000000..b280c737130
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr96814.c
@@ -0,0 +1,19 @@
+/* { dg-do run } */
+/* { dg-options "-mavx512vl -mavx512bw" } */
+/* { dg-require-effective-target avx512bw } */
+/* { dg-require-effective-target avx512vl } */
+
+typedef unsigned char __attribute__ ((__vector_size__ (32))) V;
+
+void
+test (void)
+{
+ V x = ((V){8} > 0) == 0;
+ for (unsigned i = 0; i < sizeof (x); i++)
+ if (x[i] != (i ? 0xff : 0)) __builtin_abort();
+}
+
+#define DO_TEST test
+#define AVX512VL
+#define AVX512BW
+#include "avx512-check.h"
